Portion of an off-highway truck



FIG. 1 is a front view of a portion of an off-highway truck, showing our new design;

FIG. 2 is a right view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a left view thereof;

FIG. 5 is a top view thereof;

FIG. 6 is a left, front perspective view thereof; and,

FIG. 7 is a right, front perspective view thereof.

The bottom view forms no part of the claimed design.

The elements depicted in dashed lines form no part of the ornamental design. 

The ornamental design for a portion of an off-highway truck, as shown and described. 